Piano



Feb. 26, 1929. 1,703,169

E. w. POWERS PIANO Filed July 21, 1926 4 Sheets-Sheet 1 l3? vex Z07"; .Edzvara? "(P02002151 Feb. 26, 1929. 1,703,169

, E. w. POWERS PIANO I Filed July 21, 1926 4 Sheets-Sheet 2 nu/ gia/il 4 2 l as J K\ V [i 7/ 4, A0 l 67 I K 1 v k 703,169 E. w. POWERS PIANO Filed July 2 1926 4 Sheets-Sheet 4 [iii/g ,2

Edward "(1 7 45 01- C: a 5 VJ I L/ I J flzzys,

Patented Feb. 26, 19.29

UNlTED STATES EDWARD w. POWERS, OF BOSTON, MASSACHUSETTS.

PIANO.

Application filed July 21 1926. Serial No. 123,950.

This vention relates to stringed instrurind mere particularly to pianos.

- panying driwings wherein I c, trative purp ses i enti. In:

piano type utted;

vertnral section ttlK-l-Zl on is :1 ion telzen on )f the form ofindiw bridge, herein tions;

ew oi the individir 1 shown in sectien taken on the line 9-4) of i the s a detail plan or 1 s and strut; and

section taken on the ection with var-i; nents, but in the fer to show the having a casvarious piano ate 3, a piano briefly at Fig ihodie-zl herein pre iv Q, and the r soard 7 which herein is under s exert pressure in a direction subs y perpcndicular to said board. The s; slate 3 is of substantially rigid con- :ion embodying a. head 9 for arrying s ll, 3. bearing bar and. a

anher 15.

n ed and lower plate incn'ibers 9 and ii inte 'ral rins said integral struts extending along the to) of the web porti in of the plate head 9 to unite the bearing bar 1;) and lower margin 18 the opening 17 with ribs 21 and 23 arranged i'rznsversely of said plate.

In addition to the integral struts 19 I provide separable reenforcing struts 25 which are inserted at certain sections bet ween the margin 18 and ribs :21 whereconsiderable tension is ex rted upontheplate by reason of the tightly drawn strings, and these struts are made separaoie so that they may be left out until after the springing of the plate has taken place in order to provide ample working space for the connecting up or plac i: of s .I res and particularly the individual bridge elements.

The struts 19 and 25 are herein to lie pa allel with the strings s l s '19, which as oercinbefore stated eatend over the head portion of the plate,- are designed to lie in suitable gal'is provided between certain sets of strii so as not to interfere with the activities of said strings, said integral ule or ri '2; being extremely thin as regards 'hcr transverse dimensioi s and nbstantiah 1 deep perpendienlsrly to the web of said string plate provide ample strength yet och little transverse space.

t the instrument are stretched plate desirably in the f example in a series 27 in uiddle and lower treble series 29 constitiltingbass arranged st rin 11's. m. Q 1

with the r transmitted directly to the plate and in consequence said plate caused to vibrate and produce harsh discordant metallic sounds that tend materially to destroy or at leastto drown out the purer musical tones of the instrument. To overcome these objections the tails of strings are herein resiliently mounted with respect to the string plate in a manner somewhat similar to that disclosed in my prior Patent No. 1,576,5 l5 01 March 16, 1926.

Desirably the means herein employed for 'esilientl supporting said strings are in substance cantilei' er stilts having ends or bases rigidly tired to some relatively rigid part the instrument such as the string plate 3 be tween the ends of the strings, the wiich strings are secured to the free ends of said struts and lie approximately parallel therew th that each string will be supported substantially unyieldingly in a dircctiouoit its length but capable of lateral deflection without causing any material variations in the tension of the string It is also a feature of this invention to vary the proportion, shape or character of the various struts of the instrument in order to provide just the right degree of lateral resiliency or the stability required to oppose or counterbalance the pressure exerted by the adjacent portion of the sounding board upon each string.

7 In order that the last statement may be clearly understood it should be borne in mind that the bass s rings are long and relatively massive, requiring a strut 01" maximum stiflness to Withstand the string activity and also to Withstand or balance a large portion of the entire pressure exerted by the sounding board upon the stringsdue to the arching of the board, although some of this pressure is borne by the lower treble strings which, in the usual piano construction, underlie and cross said The remaining middle and bass strings.

per treble strings are called upon to gradually diminishing degrees of sounding board pressure until at the upper end of the series where the activity of the Stllflj"? is very little, it any, board resist arse will be encountered and consequently these strings will have ahigher degr e ct freedom.

By reason of this arrangement it will be possible to maintain a condition of poise or a balance between the forces exerted by the strings under tension and the sounding board together with any additional preci re exerted by the bridge upon the sounding board, thus constituting a balance of forces that will be proportionate to the string mass and the velocity of vibration such as will promote increased harmonic activity throughout the scale of the instrument.

In carrying out this feature of the invention the cantilever struts or resilient supporting means designated generally as 30, although varying considerably in cesign, strength and character, accordi to location, have at least one common characteristic in that they are secured or fixed'rigidly to the string plate or other relatively fixed part of the instrument betwe an the ends of the strings so that all deflection of said struts will be in a direction lateral to the strings and yet the supporting ability of the struts in a longitudinal direction will not be materially reducer nor the string tension varied during string activity.

In the present embodiinei t of my invention the SQILillS for'the treble strings or unisons are esirably individual in form, but owing to he necessarily close arrangement of the trings in the upper groups, say'i er example the groups 32 and 33 of Fig. i, and to the fact that the struts for these strings have little board pressure to resist, they of rela ively small dimensions and formed with a cylindrical. base or stem 31 shouldered T he stem 31 tits an appropriate recess 33 termed in a rib 34 depending rrorn a plate which latter is secured by screws36 to the under side 45 of the string plate 3. The shoulder 32 of the strut seats against one face of the rib and re elves l strutproduced the end thrust of by the tension of the string or strings carried thereby.

in each of the groups above mentioned the struts 36 are fixed indirectly to the face of the plate 8 across which face are stretched the strings composing groups 32, 33, and 36, although it is to be understood that the invention is not limited this arrangement of securing the struts tot-he plate nor to the par ticular forms of st: uts shown.

that section of the plate where the strings are longer and heavier, as for example in the lowe treble group 28 and in thebass group 29, a more rigid and stiller strut is desirably employed because, hereinbetore stated,

these strings called upon to resist most of i the sounding board pressure. Therefore the .upuortirg meal for the series of strings 2S e i the "toil-n of an auxiliary plate 4-9, shown extending the entire length edge of tie auxiliary vlate l9 by any appropriate means, but he ein Ihey attached to the usual hitch. pin 57 secured in said auxiliary plate. 7

'll'ie bass strings29 are provided withresilient supporting means for the tail ends thereof similar tothe supporting means for the group 28, although these supporting means are materially heavier and less resilient than the former for the reason tiat said bass strings arev much longer and heavier than said strings 28. In thi connection I employ a second auxiliary plate 59 secured by screws and dowels 61 and 63 to the marginal portion 65 ot' the plate section 1", This secured edge of te second auxiliary plate 59' lies between the ends 01 the strings 29 and group and socuredby screws and dow-v els 5'1. and to the edge 5) The sounding board 7 is placed und r stress by arching the same in the frame in su manner that the pr ssure exerted by said sounding board will be d luterully to the strings stretched ucr 3,

The s ruts of the groups of strii I end 36 secured as previously stew-d J; under face 45 of the string; plate across wh the strings are strung and adjacent to iauich face the sounding board '7 is also rarren consequently the strings which are hi said struts will have u tendency said struts away from the face toward the sounding board 7, and with proper pr portioning of said struts it will be apparent that the precise amountotl' resistance-to the upward PlcSSLllfi of the sounding}; board 7 through connecting instrumentalities hereinafter GXUllllliGCl may he provided \vhereby the pressure produ ed by the tension of s d strings and the pressure of sp d soundi board will be nicely balanced, or, as her 1- bcfore stated, a condition of no se between the slings and, the sounding; board will maintained so as to promote increased hurnioni activity through the scale.

The crossing of the strire's of thewgroup 8 with those of the group 29 require u. somewhat different arrangeinenh )articularly wi" card to the resilient supports fr the str 28 which lie beneath the bass has a depressed shell 71 and the stru pl 49 secured, herein by the sc to the co 73 of said shell? which lies aboi'e upper it 1i 28, although it is to be underie invention is not limited, to the rs aborc said plate. i the auxiliary plate i a e produces an action due of "10 strings 2S tending to grate 4:9 ul'rwilrdly in the same direction iii which the pressure excr the sounding board 7 uc's upon said sti being; anoth 1' reason providi 1" c 'ut tor this group of strings than was nece, ()fl 7 sary for the strings of the groups on. end

I--1 n 236. The auxiliary strut plate loi llnee,

e strings is similarly secured, herein against the face '75 oi the depressed shelf 77 of the frame 3. It is however to be understood that the invention is not limited to the relative urrungi-unent of the strut plates and string plate h crein hown.

Any appropriate bridge means may be provided. for ope utively connecting the strings to the sounding: board, but in the present example I have shown the strings of th groups 28 and 29 connected to wooden bridges 79 W 1 i 111 Unit i p cent face of the soundr l tr u r stress so as to add to the pressure the sounding board laterally upon said string. The brid 'es 79 and 81 are herein shor-Jn oxiinately the auxiliary struts.

It is within these-ope and urpose'ol the invention to employ hitch pins similar to the hitch pins 57 and G9 of the bass and lower treble strings for securing the upper tr ble strings to their individual uts and also I employ before described. but dc r wiic are not cu upon .i c Milly to r. in main 1 board pressure and hence tr d 7 All it *icuhirly Figs 2, 3, 5, (5,

' portions of said insure the moveends in uiison with said and struts (set par and 8) and sounding bone d nients oil :3: id frc sounding board. To ind I provide 11 cans including sounding ho: rd recnforcing strip 85 of wood or other appropriate materiel s cured directly to the upper or crown face of said scunuing o2 and between it and end oteachir ndual stru 1 pie: 162-1] indi- Vic ual bridge 87, herein in the term of an an one leg; of which secured by a scr w 89 to the reenlorcing strip 85. The ther of said angle is extended upwardly and fits into a properly formed recess 91 in th under end portion of said strut, and the string supported by said strut is interlaced through the upstanding leg of said angle 87 and the end of said strut in such a manner that when tension is applied to the string; in tuning the en geeportions of the strut and un le will be i y and positiw-ly boui d lic; ,;elhcr as to prevent all rattle the surge 1;; sur- Ezzc more

ranged t' this p present exam.

- v i )le. In following cut this arrangement the end of the middle string 93 of the unison is passed thro gh an eye 95 arranged ceutr. lly of strut, 30 thence passing downwardly into a face of said strut, the ne middle string passing ue plate to one of the tunhole 97 in the upp d tuning! us 11. while the other end is looped at. 99 three. h eye 101, 103 formed in and the ol- 1 over, he adjacent end of the s rut 30 where it engages the end of the middle string and firmly binds it Within the hole 97.

of the strut is grooved along the h fodowing by loop so as to prevent t 0111 slippi of said end. l ith .nent it will be seen that as ten- A ed to the strings by the tuni pins the two parts bound by said stri" l l together in anti-"attling reia- To provide for variations in distance betveen the reenforcing strip 85 and the strut $30 one or more shiins or blocks may be i sorted at l 5 between the angle piece 7 and said strip thus providing; ineans wher a very to the arching; of board.

WVhen the struts 30 are rather subject to rapid vibration tl.ere i, sometimes danger l uee shimmering. to i stantially prevent such sbunine no at leait of said struts are ribbed at noints inter- A mediate their use and fixed ends as she in at 106, Figs. 9. these ribs tending to absorb the vibrations and also to stiffen the strut. v

The said struts 30 are also oitl'set as for GE- ainple at 107 for a purpose which will'now be ained. In this connection it will be obvious that where the base 370i the strut is supported from the inder face d5 of the string pla e as snewn in 2, 3 and 5, the t ion he strings secured to said struts \Vlrl have attendency to deflect said struts downwardly i'OVill'tl the sounding board 7 in a uranner exerted by tl string, but it the tension of treble strings is suiiicient fully or substantiall; to counteract the pressure said board the pressure exerted by the individual s uts upper l sounding board town-d the the bass and lower i toward said sounding e tendency of the strings 2'3 ay be, to bend said. struts dov-rnwa roin the face of the 'ressure niav be greater biard l and consequently .O'o a balance of forces at tea Therefore to guard against "e the position of said offset ed with regard to the face or at re ation to the strings and the strut between said o' set and bass be of such rigid construction that substantially no tier ing will result between said points but all flexing; of said strut Will take place between the point 107 which may be termed the flexto (:ounterdmlaiice the "tomes ing base of the strut and the free end thereof. in other words the location of said point 107 may be varied with different struts so as toproduce an upward movement in the direction of the arr-ow a, Fig. 7, or a downward movement in the dire Lion of the arrow 6, set i y be located. such a point as ralize any tendency on the part of lue to the tension of the string to By careful ealcu on the exact locai. be it "l'lb .ed for with the rest 1t that all diroughout the board or be reirulated to subst r of the A, lb.

strut and down :ierces serie i f na mice the force" example L strut on the oti I nieate ie body oi said 99 SLEL 3s. ithe latter case the '*h are modifications one shown in Fig. 5; are e rin the enti e support for trii t whatever presboard at that t *eing out away-at ween said ribs for portion at the length of the strut to clear the strings.

' 10 i have illustrated another form adapted to be used in cases where exerted by the sounoing board is relatively great, requirbody. I ere the strut is le so that the tentop \Ylti '6 (i n15 vided for t e 111' i said b the upper face ite'59 and prw unintentional loosening o the bolt. A1 Washer 11.? maybe herein is shown placed against the lower face of the cute. 1 109,

ere

where-in it is held by a nut 119 secured to the lower end of the bolt 111. By carefuladjust ment of the nut 113 or the screw 111 the desired 1 e to the upnart deflection of the stru' 59m be OlJi' med.

All of ti ts heroinbcfore have been i l separate plate but it is to be i vention not limited to but these struts may be made i said string plate as illustrated in F1 12.

In this embodiment astrnt plate 120 similar to the plates 19 and 0t F r. l cas integral with the marginal portion 121 of the shelf 122, WlliCll latter forms an integral part of the string plateizl. I

Strings maybesecured in theusual unannor to the edge 1230f said strut plate and a reen'torcing cushion 124 may also be used to function asdo the cushions 10!) in Fig. 4;.

In Figs. 11 and 12 a somewhat modified form of connection between the, cushion12-t and the st ut 120 is shown which includes a bridge p e which hr 1 the gap 17 of the st-rii' plate and at opposite ends respectively against the under side of the strut 120 and said'cushion 12 i.

descr bed I I The end 12 of said bridge 12.5 is posit-ioi'ied Within a depression 128 to prevent moven'ient therei A. bolt 126 adjustably secures said bridge plate to the free edge 123 of the strut 120, thus providing adjustable auxiliary support .v means therefor.

A though I have disclosed and. discussed in detail one full and complete embodiment of my invention, it-is to be understood that the invention is not limited thereto.

Claims:

1. In a stringed instrument, at least one string, relatively yielding hitching means for said string tendingto yield, when said string is under ten ion, in one direction laterally to said string, and a sounding board associated with said string, means to maintain said sounding board under stress tending to, exert pre ire laterally to said string and in 0pposition. to the forces exerted by said string whereby a substantial balance of forces may be n aintainco between said string and said sounding board.

2 In. a itringed inatrrmicnt a string sup- 7 plate, strings stretched arro:-. s said plate, resil ent supporting means interposed between at lear-at one end of the strings ilatc tending to yield laterally to and said sounding board will be established- 3. In a, stringed instrument, a'l's sup porting plate, strings stretched 'acio'ssfsaid plate, resilient supporting ncans interposed between at least 'one'end ofthe strings and plate tending to yield ,perpendicuIarly to and away from the taceofsaid plate under the tension of said strings, alsoundi ngboard associated with said strings and meansto maintain said sounding boardfunderstress to exertpressure thereon substantially equal and in opposition to the said perpendicular yielding pressure on said strings, Where-by a substantial balance of forces between those exerted by said strings and said sounding board Wlll be established.

4. In a stringed instrument, a string supporting plate, strings stretched 'acrosssaid plate, means for securingsaid to said plate including relatively resilient cantilevers Whichhave a tendenoy to yield perpendicu larly to the plane of said strings aivay from saidplate, a soundingboar d arranged adjacentto said plate, means to hold said sounding board under tension to exert pressure in '0 7 position to the direction of yield of said cantilevers, and bridge means carried by said sounding board and operatively connectedwith said strings. i

5. In a stringed instrument, a string supporting plate, strings stretched'across said plate, meansfor securing said'strings to said plate including a resilient cantilever having one end fixedto saidplate intermediate the ends of its string, said cantilever tendin yieldably to resist lateral deflections of 'sai 10o string, a sounding board operativelycoir nected with said string and means to hold said sounding board tensioned to exert pressure laterallyot' said strings and in opposition to the resistance to lateral deflection ofiered by said cantilevers.

6. In a stringed instrument, in combination, a string supporting plate, strings stretched acrosssaid plate, means for securing said strings to said plate including a re 10 silient strut rigidly secured to said plate intermediate the ends of the string, and means formed intern'iediate the ends of said strut tending to prevent shimmering of said strut duringvibrations of itsstring,

7. In a stringed instrument, in combination. a string supporting plate, strings stretched across said plate, means forsecuringsaid strings to said plate including a re silient strut rigidly secured to said: plate intermediate the ends of the string, said strut having a deflected intermediate portion tending to prevent shimmering of said'strutduring the vibrations of the string attached thereto. I I I 8. In a stringed instrument, in combination, a string supporting plate, strings stretched across said plate, n eansfor secur said struts, and bridge means ing said strings to said plate including resilient struts fixed to said plate at points intermediate the ends of their respective strings, a sounding board, a bridge secured to said sounding board, and an auxiliary bridge interposed between the free end of each of said struts andsaid bridge.

9. In astringed instrument, in combination, a string plate,strings stretched across 10 said plate, means to secure said strings to said plate including resilient struts rigidly secured to said plate at points intermediate the ends. of the strings, said struts tending to resist deflection of said strings in a direction l5 perpendicular to the ilane of: said strings,

" said plate, means to secure said strings to said plate including resilient struts rigidly secured to said plate at points intermediate the ends of the strings, said struts tending to resist deflection or said strings in a direction perpendicular to the plane oi": said strings, a

sounding board, means to cause said sounding board to exert pressure upon said strings in a perpendicular direction relative to said plane and to balance the resistive forces exerted' upon said strings by said struts, and

bridge means secured to said sounding board and held by said forces in constant engagement with said struts.

11. In a stringed instrument, in combina- 40 tion, a string plate, strings stretched across said plate, means to secure said strings to said plate including resilient struts rigidly secared to said plate at points intermediate the ends of the strings, said struts tending to resist deflection of said strings in a direction substai tially perpendicular to the plane oi said strings. a sounding board, means to cause said soundiugboard, to exert pressure upon said string in a substantially perpeiu'licular direction relative to said plane and to substantially bal: nee the resistive forces exerted, upon said strings by said struts. a wooden bridge I r "2 b 1 L '1 3 q 11 (3. P1} 1 .JQLlllQd to s..1d bfiitlltlfig o... anu rum-. .ic auxiliary bridge member interposed between said wooden bridge and said strut and held in constant engagement with said strut by one at least of said strings.

12. In a stringed instrument, string norting plate. strin s stretched across I 1 1 supsaid plate, a laterally resilient supporting strut for at least one end 01' each of said strings, means rigidly to secure said struts to the face of said plate adjacent to said strings. a sounding board, means to cause said sounding board to exert pressure upon said strings a sounding board, a bridge connecting said strut Withsaid souneingboard and means to prevent rattling between said bridge and strut.

14. In a stri 'iged instrumeit, in combination, a string supporting plate, strings stretched across said plate, means for securing said strings to said plate including a resilient strut rigi jlly seciiu'ed to said plate, a sounding board, a bridge connecting said strut with said sounding board and means to prevent rattling between said bridge and strut, including portions of a string supported by said strut.

15. Inc. stringed instrument, in combination, a string supporting plate, strings stretched across said plate, means for securing said strings t said plate including a resilient strutrigidly secured to said plate, a sounding board, a bridge connecting said strut With said rounding board and means to prevent rattling between said bridge. and strut, including portions of the string or strings supported by said strut interlaced with said strut and said bridge.

in. In a stringed instrument, in combination, a string supporting plate having an opening formed therein substantially following a. portion oil the hitch line of said plate, integral struts bridging said opening at lected intervals and separable struts bridging said opening at points intermediate said intestruts.

17. In a stringed instrument, in combination, a string supporting plate having-an opening formed therein substantially tollcu ing a portion oi the hitch line of said plate, integral. struts bridging aid opening at se lected intervals and so able reinf struts bridging said opening at points interincdiate said 11 tegral struts.

18. In a stringer instrument, in combina- Jporling plate having an string su ierein sulmtantnr follow l lion. a opening formed tl u a portion of t ie hitch line oi iid plate, llutl'i tll stru brulging .id i ".1 H

lectcd intervals and separable str i ing said opening and reinforcing saic. string p-ate ral struts. o. instrument, in cenihinm between said nte l9 Tn 5 tion, a l t a sounding board, means to maintain said sounding board under stress, series of strings stretched across said plate, and resilient supporting means for the encs of said strings arranged to maintain a concition ct poise between said strings and said sounding board by etli'ectin a substantial balauce between the string tension sure t id seunc 111g L motinp; increased harmonic actin the scale.

piano, in cembi' 'id ne; heard, a

m, a plate, a

lies 0t strin i b1) (Li r, ires o'li in c intimation, a i

' board, :1 st r of strings glate includsu port" r l' l'teractien tension and d sornding ln a 11112110, in 1 sounrhng board, a se st 11 a condition of oise l sil ien t strl lufS and sa i;L sounding); board and ted to e a sub ll equal countsractien t acting between the raid sounding 7 said strings whereby an increased lu-l act-i will be promoted thre h 23. In a piano, in combination, a plate, a plate, a )l 1 .A Y "J- aiiannee t excl-L lit,

l .nt means can veil ,city of Vibration J ial balance of the Li act t An said strings board hereby to pro mite i 1 through the scale.

piano, in cmnbination, a string s of strings stretched across s; it.

ngred to exert board rra l r" tion to said 'd string all?) report i e eneet a ul Velocity of vilu'a iou u )st balance at t e 1 r d board a id l bridge 2 to prea l board. ow

in and a sires, treble stri iii terally resilient means i tails of said strinris 'l s l\ the laterally to provide a flexible hit-en line,

eans for the lower strinejs of the I be relatively still to maintain the 'd soundi board 111 substanpressure of tial balance In a piano, a string plate, a series of strings stretched ad acent to said plate, a stressed scundmg board, laterally resilient, longitudinally rigid supporting means for bridge means interposed bestrings anr. said sounding board, I r for the lower strings use of the upper mg plate, r series of u" to said plate, means nally rigid supbridge means between, and said board, the l lly resilient, sup

ieaus fer the lower st inns being bstantially balance the oppzsllCl sounding}; board and pror: z greater degree at treeCm sunpertm means for the u 301.

L r r;

r' ngs stretched is sounding board under I? Z lfilrn-u t1 '1 1 1.1L atrial cuaic salt res lient string ruppin'ting s carried by said string; plat adapted to the pres are exerted by toward said st and means to m w [1 1 L7 1 1 t1 y,- i be sin. a L01 a 3 resilient means.

. In a stringed instrument, in combina- Jtr i plate, a series otstrings stretcher i said plate, a sounding board, means to said s-ounding board to exert pressure ly toward said strings, laterally resilng' supporting means carried by said string plate adapted to resist the pressure exerted by s id sounding board toward said strings and cushioning means to effect a bala e b the opposing forces exerted by said sounding board and said string suppcrtinp mer s.

30. in a .1 ged in trument, in combination, string supporting plate, strin 's stretched across said plate, ans "for securng said srings in plate in luding a esilient strut rigidly secured to said plate rrinediate the ends of the string, and stitup; means to med intermediate the ends d strut tending; to prevent shimmering strut during; vibrations of its string.

Ell, In a stringed instrument. in combination, a strinp; plate, a series of 'in 's stretched SH said plate, a sounding board l to exert pressure laterally tostrings. laterally resilient string ting! means carried by said string plate i d to rest-i the pressure exerted by said stein ding); beard toward said strings and rer means iaterposed between a relatively salient fixed pertion of the instrument and said laterally resilient string supporting means to rein "orce said resilient means.

n a stringed instrument, a string plate, strings stretched across one face of said plate,

and laterally yielding string supporting means fixed upon the atoresaid face of said means between said strings and said sounding heard, some at least of said supporting means each having an offset formed in its length constituting the flexing base of said supportin means and positioned relatively to its string to provide the degree of resistance esired to oppose the pressure exerted by the sounding: board that point, whereby a subsiantial belance of pressures between said strings and said sounding board will be ob tained.

In testimony whereof, I have signed my name to this specification.

EDWARD W. POWERS,

GERTIFIGATE OF CORRECTION. Patent No. 1,703,169. Granted February 26, 1929, to

EDWARD W. POWERS.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1. line 75, for the word "springing" read "stringing"; page 7, line 109, claim 30, 'for the word "in" read "to"; and that the said Letters Patent should be read with these corrections therein that the same may conform to tize record of the case in the Patent Office.

Signed and sealed this 26th day of March, A. D. 1929.

M. J. Moore, (Seal) Acting Commissioner of Patents- 

